/*  ADMesh -- process triangulated solid meshes
 *  Copyright (C) 1995, 1996  Anthony D. Martin <amartin@engr.csulb.edu>
 *  Copyright (C) 2013, 2014  several contributors, see AUTHORS
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.

 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.

 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 *  Questions, comments, suggestions, etc to
 *           https://github.com/admesh/admesh/issues
 */

#ifndef __admesh_stl__
#define __admesh_stl__

#include <stdio.h>
#include <stdint.h>
#include <stddef.h>

#include <Eigen/Geometry> 

// Size of the binary STL header, free form.
#define LABEL_SIZE             80
// Binary STL, length of the "number of faces" counter.
#define NUM_FACET_SIZE         4
// Binary STL, sizeof header + number of faces.
#define HEADER_SIZE            84
#define STL_MIN_FILE_SIZE      284
#define ASCII_LINES_PER_FACET  7

typedef Eigen::Matrix<float, 3, 1, Eigen::DontAlign> stl_vertex;
typedef Eigen::Matrix<float, 3, 1, Eigen::DontAlign> stl_normal;
static_assert(sizeof(stl_vertex) == 12, "size of stl_vertex incorrect");
static_assert(sizeof(stl_normal) == 12, "size of stl_normal incorrect");

typedef struct {
  stl_normal normal;
  stl_vertex vertex[3];
  char       extra[2];
} stl_facet;
#define SIZEOF_STL_FACET       50

static_assert(offsetof(stl_facet, normal) == 0, "stl_facet.normal has correct offset");
static_assert(offsetof(stl_facet, vertex) == 12, "stl_facet.vertex has correct offset");
static_assert(offsetof(stl_facet, extra ) == 48, "stl_facet.extra has correct offset");
static_assert(sizeof(stl_facet) >= SIZEOF_STL_FACET, "size of stl_facet incorrect");

typedef enum {binary, ascii, inmemory} stl_type;

typedef struct {
  stl_vertex p1;
  stl_vertex p2;
  int        facet_number;
} stl_edge;

typedef struct stl_hash_edge {
  // Key of a hash edge: sorted vertices of the edge.
  uint32_t       key[6];
  // Compare two keys.
  bool operator==(const stl_hash_edge &rhs) { return memcmp(key, rhs.key, sizeof(key)) == 0; }
  bool operator!=(const stl_hash_edge &rhs) { return ! (*this == rhs); }
  int  hash(int M) const { return ((key[0] / 11 + key[1] / 7 + key[2] / 3) ^ (key[3] / 11  + key[4] / 7 + key[5] / 3)) % M; }
  // Index of a facet owning this edge.
  int            facet_number;
  // Index of this edge inside the facet with an index of facet_number.
  // If this edge is stored backwards, which_edge is increased by 3.
  int            which_edge;
  struct stl_hash_edge  *next;
} stl_hash_edge;

typedef struct {
  // Index of a neighbor facet.
  int   neighbor[3];
  // Index of an opposite vertex at the neighbor face.
  char  which_vertex_not[3];
} stl_neighbors;

typedef struct {
  int   vertex[3];
} v_indices_struct;

typedef struct {
  char          header[81];
  stl_type      type;
  uint32_t      number_of_facets;
  stl_vertex    max;
  stl_vertex    min;
  stl_vertex    size;
  float         bounding_diameter;
  float         shortest_edge;
  float         volume;
  unsigned      number_of_blocks;
  int           connected_edges;
  int           connected_facets_1_edge;
  int           connected_facets_2_edge;
  int           connected_facets_3_edge;
  int           facets_w_1_bad_edge;
  int           facets_w_2_bad_edge;
  int           facets_w_3_bad_edge;
  int           original_num_facets;
  int           edges_fixed;
  int           degenerate_facets;
  int           facets_removed;
  int           facets_added;
  int           facets_reversed;
  int           backwards_edges;
  int           normals_fixed;
  int           number_of_parts;
  int           malloced;
  int           freed;
  int           facets_malloced;
  int           collisions;
  int           shared_vertices;
  int           shared_malloced;
} stl_stats;

typedef struct {
  FILE          *fp;
  stl_facet     *facet_start;
  stl_edge      *edge_start;
  stl_hash_edge **heads;
  stl_hash_edge *tail;
  int           M;
  stl_neighbors *neighbors_start;
  v_indices_struct *v_indices;
  stl_vertex    *v_shared;
  stl_stats     stats;
  char          error;
} stl_file;


extern void stl_open(stl_file *stl, const char *file);
extern void stl_close(stl_file *stl);
extern void stl_stats_out(stl_file *stl, FILE *file, char *input_file);
extern void stl_print_edges(stl_file *stl, FILE *file);
extern void stl_print_neighbors(stl_file *stl, char *file);
extern void stl_put_little_int(FILE *fp, int value_in);
extern void stl_put_little_float(FILE *fp, float value_in);
extern void stl_write_ascii(stl_file *stl, const char *file, const char *label);
extern void stl_write_binary(stl_file *stl, const char *file, const char *label);
extern void stl_write_binary_block(stl_file *stl, FILE *fp);
extern void stl_check_facets_exact(stl_file *stl);
extern void stl_check_facets_nearby(stl_file *stl, float tolerance);
extern void stl_remove_unconnected_facets(stl_file *stl);
extern void stl_write_vertex(stl_file *stl, int facet, int vertex);
extern void stl_write_facet(stl_file *stl, char *label, int facet);
extern void stl_write_edge(stl_file *stl, char *label, stl_hash_edge edge);
extern void stl_write_neighbor(stl_file *stl, int facet);
extern void stl_write_quad_object(stl_file *stl, char *file);
extern void stl_verify_neighbors(stl_file *stl);
extern void stl_fill_holes(stl_file *stl);
extern void stl_fix_normal_directions(stl_file *stl);
extern void stl_fix_normal_values(stl_file *stl);
extern void stl_reverse_all_facets(stl_file *stl);
extern void stl_translate(stl_file *stl, float x, float y, float z);
extern void stl_translate_relative(stl_file *stl, float x, float y, float z);
extern void stl_scale_versor(stl_file *stl, const stl_vertex &versor);
inline void stl_scale(stl_file *stl, float factor) { stl_scale_versor(stl, stl_vertex(factor, factor, factor)); }
extern void stl_rotate_x(stl_file *stl, float angle);
extern void stl_rotate_y(stl_file *stl, float angle);
extern void stl_rotate_z(stl_file *stl, float angle);
extern void stl_mirror_xy(stl_file *stl);
extern void stl_mirror_yz(stl_file *stl);
extern void stl_mirror_xz(stl_file *stl);
extern void stl_transform(stl_file *stl, float *trafo3x4);
extern void stl_transform(stl_file *stl, const Eigen::Transform<double, 3, Eigen::Affine, Eigen::DontAlign>& t);
extern void stl_open_merge(stl_file *stl, char *file);
extern void stl_invalidate_shared_vertices(stl_file *stl);
extern void stl_generate_shared_vertices(stl_file *stl);
extern void stl_write_obj(stl_file *stl, const char *file);
extern void stl_write_off(stl_file *stl, const char *file);
extern void stl_write_dxf(stl_file *stl, const char *file, char *label);
extern void stl_write_vrml(stl_file *stl, const char *file);
inline void stl_calculate_normal(stl_normal &normal, stl_facet *facet) {
  normal = (facet->vertex[1] - facet->vertex[0]).cross(facet->vertex[2] - facet->vertex[0]);
}
inline void stl_normalize_vector(stl_normal &normal) {
  double length = normal.cast<double>().norm();
  if (length < 0.000000000001)
    normal = stl_normal::Zero();
  else
    normal *= float(1.0 / length);
}
inline bool stl_vertex_lower(const stl_vertex &a, const stl_vertex &b) {
  return (a(0) != b(0)) ? (a(0) < b(0)) :
        ((a(1) != b(1)) ? (a(1) < b(1)) : (a(2) < b(2)));
}
extern void stl_calculate_volume(stl_file *stl);

extern void stl_repair(stl_file *stl, int fixall_flag, int exact_flag, int tolerance_flag, float tolerance, int increment_flag, float increment, int nearby_flag, int iterations, int remove_unconnected_flag, int fill_holes_flag, int normal_directions_flag, int normal_values_flag, int reverse_all_flag, int verbose_flag);

extern void stl_initialize(stl_file *stl);
extern void stl_count_facets(stl_file *stl, const char *file);
extern void stl_allocate(stl_file *stl);
extern void stl_read(stl_file *stl, int first_facet, bool first);
extern void stl_facet_stats(stl_file *stl, stl_facet facet, bool &first);
extern void stl_reallocate(stl_file *stl);
extern void stl_add_facet(stl_file *stl, stl_facet *new_facet);
extern void stl_get_size(stl_file *stl);

extern void stl_clear_error(stl_file *stl);
extern int stl_get_error(stl_file *stl);
extern void stl_exit_on_error(stl_file *stl);

#endif
